1. Field of the Invention
The present invention relates to a television system using a narrow bandwidth, for transmitting and receiving high definition, quality television images and sounds.
2. Description of the Prior Art
Standard television has been restricted to the NTSC television standard for transmission of television for many years. The concepts of raster-scanning and interleaving of frames have produced complex and expensive equipment for studios and home TV receivers alike. The conversion to digital TV has been delayed due to bandwidth limitations on existing distribution channels (e.g., broadcast, cable satellite, etc.). Compression of digital TV signals has produced impressive reduction in bandwidths but is not capable of producing high definition digital TV on existing broadcast frequencies without significantly degrading image quality. Existing digital TV consists primarily of sending digital or compressed digital picture and sound signals with synchronizing data in a wide bandwidth signal.
Present TV resolutions need to be improved for increasing consumer requirements. The proposed FCC standard for digital TV requires a 6 MHz bandwidth and involves interlaced and non-interlaced scanned images. This type of system requires multiple repeats of non-changing image areas or compression techniques which reduce the amount of redundant data needed to reproduce images at the receiver location. Considerable overhead, and some loss of picture quality is inherent in these compression techniques such as JPEG (joint photographic experts group) and MPEG (motion picture experts group). The following patent documents are exemplary citations of the above.
U.S. Pat. No. 5,179,442, issued Jan. 12, 1993 to Azadegan et al., discloses a HDTV (high definition television) system compresses the augmentation channel for digital transmission using a QPSK (quadraphase shift keying) compression scheme to reduce the required power on a narrow RF channel having a 3 MHz wide bandwidth. U.S. Pat. No. 5,181,229, issued Jan. 19, 1993 to Langlais et al., describes a data transmission and receiving arrangement utilizing statistic coding by converting digital samples into statistic codewords intermeshed with synchronizing words. U.S. Pat. No. 5,184,218, issued Feb. 2, 1993 to Gerdes, describes a system for interpolating and extrapolating video signals for transmission, in compressed format, for HDTV. U.S. Pat. No. 5,231,486, issued Jul. 27, 1993 to Acampora et al., discloses an HDTV compression system that utilizes a processor for identifying variable length codewords in a data bitstream. Upon the identification, the processor determines whether the codeword is a high priority or standard priority, and ultimately packs the codeword into a respective data packer according to the determined priority type.
U.S. Pat. No. 5,270,813, issued Dec. 14, 1993 to Puri et al., describes an adaptive video encoding and decoding technique which facilitates the transmission, reception, storage, or retrieval of a scalable video signal. The scaling can be realized by adaptively encoding a video signal which is selectively taken from multiplicity of predictions obtained from previously decoded images and of compatible predictions obtained from up-sampling lower resolution decoded images of the current temporal reference. U.S. Pat. No. 5,285,276, issued Feb. 8, 1994 to Citta, describes a bi-rate HDTV signal transmission that compresses each frame of video signal into either a four-level or a two-level data segments, having an established partition between the segments dependent on the effective level of compression. U.S. Pat. No. 5,301,242, issued Apr. 5, 1994 to Gonzales et al., discloses an apparatus and method for encoding still and motion pictures using adaptive quantization in a compression transform technique in order to preserve or improve the quality of the compression.
U.S. Pat. No. 5,311,308, issued May 10, 1994 to Bernard, discloses a method and device for encoding and decoding an HDTV signals so that the broadcasting of HD images in the 16/9 format in a narrow bandwidth outperforms the HD MAC type channel and transmission over a ground wire network or short wave link network. U.S. Pat. No. 5,335,017, issued Aug. 2, 1994 to Brasoveanu et al., discloses an HDTV system that defines the pixels of the images with three equations, such that only the coefficients of the equations need be transmitted, and then only the coefficients of the changing pixels need be transmitted. The remaining portion of the image, i.e., the unchanging pixels, follow a pre-sent set of coefficients. U.S. Pat. No. 5,351,083, issued Sep. 27, 1994 to Tsukagoshi, discloses a system for encoding and/or decoding fast and slow motion region blocks of an image. The system makes a majority decision whether to replace the predetermined block with a surrounding block, thereby enhancing picture quality.
U.S. Pat. No. 5,444,490, issued Aug. 22, 1995 to de With et al., describes a system for producing images of a HDTV system into codeword that remove the complexity of decoding such that the images are more easily retrieved and the quality of the transmission is not diminished. U.S. Pat. No. 5,448,568, issued Sep. 5, 1995 to Delpuch et al., describes an interactive TV transmission system which utilizes compressed audio and video programs that form the transport packets. Video packets, audio packets and application packets are time division multiplexed for transmission or storage. U.S. Pat. No. 5,457,495, issued Oct. 10, 1995 to Hartung, discloses a method of coding a video signal at a fixed bit rate by vector quantizing the signal in an adaptive video coder; this provides a codebook that is updated by comprising coding error of a first frame with the coding error of a next frame. U.K. Patent Document No. 2,271,253, published Apr. 6, 1994 to Wilson, discloses a computer workstation having a video conferencing communication system therein for use in a LAN and having software support modules for processing video data in bit map form in order to provide compatibility between non-compatible hardware formats.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.